One less dose of HPV vaccine to prevent cancer
Authors: Diane M Harper, Marie Claire O'Dwyer
Journal: The Lancet Public Health (2023)

The landmark research by Élodie Bénard and colleagues in this issue of The Lancet Public Health supports one less dose of human papillomavirus (HPV) vaccine than is currently approved for children aged 9–14 years.1Bénard E Drolet M Laprise J-F et al.Potential population-level effectiveness of one-dose HPV vaccination in low-income and middle-income countries: a mathematical modelling analysis.Lancet Public Health. 2023; 8: e788-e799Google Scholar Around 125 countries have introduced HPV vaccines for girls aged 9–14 years. Seven countries will introduce programmes in 2023.2UNICEFClosing the gap: UNICEF bolsters country efforts to increase HPV vaccination.https://www.unicef.org/supply/stories/closing-gap-unicef-bolsters-country-efforts-increase-hpv-vaccinationDate: 2023Date accessed: September 2, 2023Google Scholar Building on the accumulating data that show the comparative efficacy and immunogenicity of one dose of HPV vaccine compared with two, Bénard and colleagues report compelling data supporting a one-dose vaccine strategy. The comprehensive modelling in this study assumes a minimum duration of protection for the single HPV dose of 20 years. The opportunity to move to one dose offers significant advantages in cost saving and administrative simplicity. With vaccination starting at 9 years of age, the antibody efficacy will prevent infections until women reach their local screening age, possibly longer. There are, naturally, potential pitfalls with changing public-health immunisation recommendations. There are 195 countries in the world, and 125 have HPV vaccination programmes that are likely to move to a one-dose programme. The messaging of this change is crucial. Policy changes could undermine trust and increase vaccine hesitancy.3Carrieri V Guthmuller S Wübker A Trust and COVID-19 vaccine hesitancy.Sci Rep. 2023; 139245Crossref Scopus (2) Google Scholar The duration of protection from HPV infection is central to the success of a one-dose HPV vaccine strategy. Current data have not shown any protection waning up to 12 years after a single dose.4Kjaer SK Nygård M Sundström K et al.Final analysis of a 14-year long-term follow-up study of the effectiveness and immunogenicity of the quadrivalent human papillomavirus vaccine in women from four Nordic countries.EClinicalMedicine. 2020; 23100401Summary Full Text Full Text PDF PubMed Scopus (68) Google Scholar, 5Porras C Tsang SH Herrero R et al.Efficacy of the bivalent HPV vaccine against HPV 16/18-associated precancer: long-term follow-up results from the Costa Rica Vaccine Trial.Lancet Oncol. 2020; 21: 1643-1652Summary Full Text Full Text PDF PubMed Scopus (36) Google Scholar If efficacy suddenly drops in the next decade, Bénard and colleagues' modelling suggests strategies necessary to avoid reductions in cancer prevention protection. Assuming protection extends beyond 20 years with one dose, the modelling study shows the efficacy of simplifying the HPV vaccination strategy. A simplified, one-dose vaccination strategy with a safe and trusted HPV vaccine can expand vaccine access, address disparities in vaccination, and help rebuild public-health trust. Childhood HPV vaccination, followed by adulthood HPV screening, puts WHO's cervical cancer elimination goal within reach. Both vaccination and screening are rooted in the science of HPV, a prophylactic vaccine and the most sensitive and specific test for cervical cancer screening ever created. Cervical cancer is the first to use causal biomarkers, not visual disturbances, for more effective screening. Even with the advances in cervical cancer prevention and screening, the diseases incidence remains stubbornly high, and two in three women aged 30–49 years have never been screened for cervical cancer.6Bruni L Serrano B Roura E et al.Cervical cancer screening programmes and age-specific coverage estimates for 202 countries and territories worldwide: a review and synthetic analysis.Lancet Glob Health. 2022; 10: e1115-e1127Summary Full Text Full Text PDF PubMed Scopus (59) Google Scholar Global screening programmes initiated at different ages consist of different techniques and differ in the number of lifetime screens and screening intervals. Of the 139 countries with official recommendations for cervical cancer screening, primary HPV screening starts at 30 years of age for all the upper middle-income countries, lower middle-income countries, and low-income countries, and 96% of high-income countries.6Bruni L Serrano B Roura E et al.Cervical cancer screening programmes and age-specific coverage estimates for 202 countries and territories worldwide: a review and synthetic analysis.Lancet Glob Health. 2022; 10: e1115-e1127Summary Full Text Full Text PDF PubMed Scopus (59) Google Scholar Primary HPV screening is repeated at 5-year intervals for nearly 80% of all these countries.6Bruni L Serrano B Roura E et al.Cervical cancer screening programmes and age-specific coverage estimates for 202 countries and territories worldwide: a review and synthetic analysis.Lancet Glob Health. 2022; 10: e1115-e1127Summary Full Text Full Text PDF PubMed Scopus (59) Google Scholar Unfortunately, the effect on cervical cancer prevention will not be measurable for 30–40 years after vaccination if no emphasis on screening is established. Only with primary HPV screening implemented every 5 years, with follow-up for abnormal screens, will one-dose HPV vaccination programmes successfully achieve the rapid decrease in cervical cancers required to reach an elimination goal.7Hall MT Simms KT Lew JB et al.The projected timeframe until cervical cancer elimination in Australia: a modelling study.Lancet Public Health. 2019; 4: e19-e27Summary Full Text Full Text PDF PubMed Scopus (240) Google Scholar The WHO Cervical Cancer Elimination Goal is for 90% of girls aged 9–14 years to be vaccinated, 70% of all women to be screened first at 35 years and then 45 years, and 90% of those with cervical precancers or cancers to receive treatment.8Singh D Vignat J Lorenzoni V et al.Global estimates of incidence and mortality of cervical cancer in 2020: a baseline analysis of the WHO Global Cervical Cancer Elimination Initiative.Lancet Glob Health. 2023; 11: e197-e206Summary Full Text Full Text PDF PubMed Scopus (0) Google Scholar Bénard and colleagues' modelling study shows the power of one less dose. One less HPV vaccine dose simplifies the childhood immunisation programme more than any other childhood vaccination strategy, reduces the cost of vaccination and the organisational tracking requirement for call-back vaccinations, might double the number of girls vaccinated against HPV in countries that implement one-dose strategies, and facilitates catch-up programmes for those aged out of vaccination during the pandemic. One less dose is one step closer to cervical cancer elimination. We declare no competing interests. Potential population-level effectiveness of one-dose HPV vaccination in low-income and middle-income countries: a mathematical modelling analysisOne-dose routine vaccination could avert most of the cervical cancers averted with two-dose vaccination while being more efficient, provided the duration of one-dose protection is greater than 20–30 years (depending on the LMIC). The doses saved by introducing one-dose routine vaccination could offer the opportunity to vaccinate girls before they age out of the vaccination window of 9–14 years and, potentially, to vaccinate boys or older age groups. Full-Text PDF Open Access